/* $OpenBSD: trap.c,v 1.54 2007/05/15 13:46:22 martin Exp $ */ /* $NetBSD: trap.c,v 1.68 1998/12/22 08:47:07 scottr Exp $ */ /* * Copyright (c) 1988 University of Utah. * Copyright (c) 1982, 1986, 1990, 1993 * The Regents of the University of California. All rights reserved. * * This code is derived from software contributed to Berkeley by * the Systems Programming Group of the University of Utah Computer * Science Department. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * from: Utah $Hdr: trap.c 1.37 92/12/20$ * * @(#)trap.c 8.5 (Berkeley) 1/4/94 */ #include #include #include #include #include #include #include #include #include #include #ifdef KGDB #include #endif #ifdef KTRACE #include #endif #ifdef DEBUG #include #endif #include #include #include #include #include #include #include "systrace.h" #include #include #include #ifdef COMPAT_SUNOS #include extern struct emul emul_sunos; #endif int astpending; char *trap_type[] = { "Bus error", "Address error", "Illegal instruction", "Zero divide", "CHK instruction", "TRAPV instruction", "Privilege violation", "Trace trap", "MMU fault", "SSIR trap", "Format error", "68881 exception", "Coprocessor violation", "Async system trap" }; int trap_types = sizeof trap_type / sizeof trap_type[0]; /* * Size of various exception stack frames (minus the standard 8 bytes) */ short exframesize[] = { FMT0SIZE, /* type 0 - normal (68020/030/040) */ FMT1SIZE, /* type 1 - throwaway (68020/030/040) */ FMT2SIZE, /* type 2 - normal 6-word (68020/030/040) */ FMT3SIZE, /* type 3 - FP post-instruction (68040) */ FMT4SIZE, /* type 4 - LC040 FP exception (68LC040) */ -1, -1, /* type 5-6 - undefined */ FMT7SIZE, /* type 7 - access error (68040) */ 58, /* type 8 - bus fault (68010) */ FMT9SIZE, /* type 9 - coprocessor mid-instruction (68020/030) */ FMTASIZE, /* type A - short bus fault (68020/030) */ FMTBSIZE, /* type B - long bus fault (68020/030) */ -1, -1, -1, -1 /* type C-F - undefined */ }; #ifdef M68040 #define KDFAULT(c) (mmutype == MMU_68040 ? \ ((c) & SSW4_TMMASK) == SSW4_TMKD : \ ((c) & (SSW_DF|SSW_FCMASK)) == (SSW_DF|FC_SUPERD)) #define WRFAULT(c) (mmutype == MMU_68040 ? \ ((c) & SSW4_RW) == 0 : \ ((c) & (SSW_DF|SSW_RW)) == SSW_DF) #else #define KDFAULT(c) (((c) & (SSW_DF|SSW_FCMASK)) == (SSW_DF|FC_SUPERD)) #define WRFAULT(c) (((c) & (SSW_DF|SSW_RW)) == SSW_DF) #endif #ifdef DEBUG int mmudebug = 0; int mmupid = -1; #define MDB_FOLLOW 1 #define MDB_WBFOLLOW 2 #define MDB_WBFAILED 4 #define MDB_ISPID(pid) ((pid) == mmupid) #endif /* trap() and syscall() only called from locore */ void trap(int, u_int, u_int, struct frame); void syscall(register_t, struct frame); #if defined(M68040) int writeback(struct frame *); void wb_userret(struct proc *, struct frame *); #if DEBUG static void dumpssw(u_short); static void dumpwb(int, u_short, u_int, u_int); #endif #endif /* * Trap and syscall both need the following work done before returning * to user mode. */ void userret(struct proc *p) { int sig; /* take pending signals */ while ((sig = CURSIG(p)) != 0) postsig(sig); curcpu()->ci_schedstate.spc_curpriority = p->p_priority = p->p_usrpri; } #ifdef M68040 /* * Same as above, but also handles writeback completion on 68040. */ void wb_userret(struct proc *p, struct frame *fp) { int sig; union sigval sv; /* take pending signals */ while ((sig = CURSIG(p)) != 0) postsig(sig); p->p_priority = p->p_usrpri; /* * Deal with user mode writebacks (from trap, or from sigreturn). * If any writeback fails, go back and attempt signal delivery * unless we have already been here and attempted the writeback * (e.g. bad address with user ignoring SIGSEGV). In that case, * we just return to the user without successfully completing * the writebacks. Maybe we should just drop the sucker? */ if (mmutype == MMU_68040 && fp->f_format == FMT7) { if ((sig = writeback(fp)) != 0) { sv.sival_ptr = (void *)fp->f_fmt7.f_fa; trapsignal(p, sig, T_MMUFLT, SEGV_MAPERR, sv); while ((sig = CURSIG(p)) != 0) postsig(sig); p->p_priority = p->p_usrpri; } } curcpu()->ci_schedstate.spc_curpriority = p->p_priority; } #endif /* * Trap is called from locore to handle most types of processor traps, * including events such as simulated software interrupts/AST's. * System calls are broken out for efficiency. */ /*ARGSUSED*/ void trap(type, code, v, frame) int type; u_int code; u_int v; struct frame frame; { struct proc *p; int i, s; u_int ucode; int typ = 0; union sigval sv; uvmexp.traps++; p = curproc; ucode = 0; /* I have verified that this DOES happen! -gwr */ if (p == NULL) p = &proc0; #ifdef DIAGNOSTIC if (p->p_addr == NULL) panic("trap: type 0x%x, code 0x%x, v 0x%x -- no pcb", type, code, v); #endif if (USERMODE(frame.f_sr)) { type |= T_USER; p->p_md.md_regs = frame.f_regs; } switch (type) { default: dopanic: printf("trap type %d, code = 0x%x, v = 0x%x\n", type, code, v); printf("%s program counter = 0x%x\n", (type & T_USER) ? "user" : "kernel", frame.f_pc); /* * Let the kernel debugger see the trap frame that * caused us to panic. This is a convenience so * one can see registers at the point of failure. */ s = splhigh(); #ifdef KGDB /* If connected, step or cont returns 1 */ if (kgdb_trap(type, (db_regs_t *)&frame)) goto kgdb_cont; #endif #ifdef DDB (void)kdb_trap(type, (db_regs_t *)&frame); #endif #ifdef KGDB kgdb_cont: #endif splx(s); if (panicstr) { printf("trap during panic!\n"); #ifdef DEBUG /* XXX should be a machine-dependent hook */ printf("(press a key)\n"); (void)cngetc(); #endif } regdump(&(frame.F_t), 128); type &= ~T_USER; if ((u_int)type < trap_types) panic(trap_type[type]); panic("trap"); case T_BUSERR: /* Kernel bus error */ if (!p->p_addr->u_pcb.pcb_onfault) goto dopanic; /* * If we have arranged to catch this fault in any of the * copy to/from user space routines, set PC to return to * indicated location and set flag informing buserror code * that it may need to clean up stack frame. */ copyfault: frame.f_stackadj = exframesize[frame.f_format]; frame.f_format = frame.f_vector = 0; frame.f_pc = (int)p->p_addr->u_pcb.pcb_onfault; return; case T_BUSERR|T_USER: /* Bus error */ typ = BUS_OBJERR; ucode = code & ~T_USER; i = SIGBUS; break; case T_ADDRERR|T_USER: /* Address error */ typ = BUS_ADRALN; ucode = code & ~T_USER; i = SIGBUS; break; case T_ILLINST|T_USER: /* Illegal instruction fault */ ucode = frame.f_format; /* XXX was ILL_PRIVIN_FAULT */ typ = ILL_ILLOPC; i = SIGILL; v = frame.f_pc; break; case T_PRIVINST|T_USER: /* Privileged instruction fault */ ucode = frame.f_format; /* XXX was ILL_PRIVIN_FAULT */ typ = ILL_PRVOPC; i = SIGILL; v = frame.f_pc; break; /* * divde by zero, CHK/TRAPV inst */ case T_ZERODIV|T_USER: /* Divide by zero trap */ ucode = frame.f_format; typ = FPE_INTDIV; i = SIGFPE; v = frame.f_pc; break; case T_CHKINST|T_USER: /* CHK instruction trap */ ucode = frame.f_format; type = FPE_FLTSUB; i = SIGFPE; v = frame.f_pc; break; case T_TRAPVINST|T_USER: /* TRAPV instruction trap */ ucode = frame.f_format; typ = ILL_ILLTRP; i = SIGILL; v = frame.f_pc; break; /* * User coprocessor violation */ case T_COPERR|T_USER: typ = ILL_COPROC; ucode = 0; i = SIGILL; break; /* * 6888x exceptions */ case T_FPERR|T_USER: typ = FPE_FLTRES; ucode = code; i = SIGFPE; v = frame.f_pc; break; /* * FPU faults in supervisor mode. */ case T_ILLINST: /* fnop generates this, apparently. */ case T_FPEMULI: case T_FPEMULD: { extern label_t *nofault; if (nofault) /* If we're probing. */ longjmp(nofault); if (type == T_ILLINST) printf("Kernel Illegal Instruction trap.\n"); else printf("Kernel FPU trap.\n"); goto dopanic; } /* * Unimplemented FPU instructions/datatypes. */ case T_FPEMULI|T_USER: case T_FPEMULD|T_USER: #ifdef FPU_EMULATE i = fpu_emulate(&frame, &p->p_addr->u_pcb.pcb_fpregs, &typ); /* XXX -- deal with tracing? (frame.f_sr & PSL_T) */ if (i == 0) goto out; #else uprintf("pid %d killed: no floating point support.\n", p->p_pid); i = SIGILL; typ = ILL_COPROC; #endif ucode = frame.f_format; v = frame.f_pc; break; case T_COPERR: /* Kernel coprocessor violation */ case T_FMTERR: /* Kernel format error */ case T_FMTERR|T_USER: /* User format error */ /* * The user has most likely trashed the RTE or FP state info * in the stack frame of a signal handler. */ printf("pid %d: kernel %s exception\n", p->p_pid, type==T_COPERR ? "coprocessor" : "format"); type |= T_USER; p->p_sigacts->ps_sigact[SIGILL] = SIG_DFL; i = sigmask(SIGILL); p->p_sigignore &= ~i; p->p_sigcatch &= ~i; p->p_sigmask &= ~i; i = SIGILL; ucode = frame.f_format; /* XXX was ILL_RESAD_FAULT */ typ = ILL_COPROC; v = frame.f_pc; break; /* * XXX: Trace traps are a nightmare. * * HP-UX uses trap #1 for breakpoints, * OpenBSD/m68k uses trap #2, * SUN 3.x uses trap #15, * DDB and KGDB uses trap #15 (for kernel breakpoints; * handled elsewhere). * * OpenBSD and HP-UX traps both get mapped by locore.s into T_TRACE. * SUN 3.x traps get passed through as T_TRAP15 and are not really * supported yet. * * XXX: We should never get kernel-mode T_TRACE or T_TRAP15 * XXX: because locore.s now gives them special treatment. */ case T_TRAP15: /* kernel breakpoint */ frame.f_sr &= ~PSL_T; return; case T_TRACE|T_USER: /* user trace trap */ #ifdef COMPAT_SUNOS /* * SunOS uses Trap #2 for a "CPU cache flush" * Just flush the on-chip caches and return. * XXX - Too bad OpenBSD uses trap 2... */ if (p->p_emul == &emul_sunos) { ICIA(); DCIU(); /* get out fast */ return; } #endif /* FALLTHROUGH */ case T_TRACE: /* Kernel trace trap */ case T_TRAP15|T_USER: /* Sun user trace trap */ frame.f_sr &= ~PSL_T; i = SIGTRAP; typ = TRAP_TRACE; break; case T_ASTFLT: /* System async trap, cannot happen */ goto dopanic; case T_ASTFLT|T_USER: /* User async trap. */ astpending = 0; /* * We check for software interrupts first. This is because * they are at a higher level than ASTs, and on a VAX would * interrupt the AST. We assume that if we are processing * an AST that we must be at IPL0 so we don't bother to * check. Note that we ensure that we are at least at SIR * IPL while processing the SIR. */ splsoft(); /* FALLTHROUGH */ case T_SSIR: /* Software interrupt */ case T_SSIR|T_USER: if (ssir & SIR_SERIAL) { void zssoft(int); siroff(SIR_SERIAL); uvmexp.softs++; zssoft(0); } if (ssir & SIR_NET) { void netintr(void); siroff(SIR_NET); uvmexp.softs++; netintr(); } if (ssir & SIR_CLOCK) { void softclock(void); siroff(SIR_CLOCK); uvmexp.softs++; softclock(); } if (ssir & SIR_ADB) { void adb_soft_intr(void); siroff(SIR_ADB); uvmexp.softs++; adb_soft_intr(); } /* * If this was not an AST trap, we are all done. */ if (type != (T_ASTFLT|T_USER)) { uvmexp.traps--; return; } spl0(); if (p->p_flag & P_OWEUPC) { ADDUPROF(p); } if (type == (T_ASTFLT | T_USER) && want_resched) { preempt(NULL); } goto out; case T_MMUFLT: /* Kernel mode page fault */ case T_MMUFLT|T_USER: /* page fault */ { vaddr_t va; struct vmspace *vm = p->p_vmspace; struct vm_map *map; int rv; vm_prot_t ftype, vftype; extern struct vm_map *kernel_map; #ifdef DEBUG if ((mmudebug & MDB_WBFOLLOW) || MDB_ISPID(p->p_pid)) printf("trap: T_MMUFLT pid=%d, code=%x, v=%x, pc=%x, sr=%x\n", p->p_pid, code, v, frame.f_pc, frame.f_sr); #endif /* * It is only a kernel address space fault iff: * 1. (type & T_USER) == 0 and * 2. pcb_onfault not set or * 3. pcb_onfault set but supervisor data fault * The last can occur during an exec() copyin where the * argument space is lazy-allocated. */ if ((type & T_USER) == 0 && (!p->p_addr->u_pcb.pcb_onfault || KDFAULT(code))) map = kernel_map; else map = vm ? &vm->vm_map : kernel_map; if (WRFAULT(code)) { vftype = VM_PROT_WRITE; ftype = VM_PROT_READ | VM_PROT_WRITE; } else vftype = ftype = VM_PROT_READ; va = trunc_page((vaddr_t)v); if (map == kernel_map && va == 0) { printf("trap: bad kernel %s access at 0x%x\n", (ftype & VM_PROT_WRITE) ? "read/write" : "read", v); goto dopanic; } rv = uvm_fault(map, va, 0, ftype); #ifdef DEBUG if (rv && MDB_ISPID(p->p_pid)) printf("uvm_fault(%p, 0x%lx, 0, 0x%x) -> 0x%x\n", map, va, ftype, rv); #endif /* * If this was a stack access, we keep track of the maximum * accessed stack size. Also, if vm_fault gets a protection * failure, it is due to accessing the stack region outside * the current limit and we need to reflect that as an access * error. */ if ((vm != NULL && (caddr_t)va >= vm->vm_maxsaddr) && map != kernel_map) { if (rv == 0) uvm_grow(p, va); else if (rv == EACCES) rv = EFAULT; } if (rv == 0) { if (type == T_MMUFLT) { #if defined(M68040) if (mmutype == MMU_68040) (void)writeback(&frame); #endif return; } goto out; } if (type == T_MMUFLT) { if (p->p_addr->u_pcb.pcb_onfault) goto copyfault; printf("uvm_fault(%p, 0x%lx, 0, 0x%x) -> 0x%x\n", map, va, ftype, rv); printf(" type %x, code [mmu,,ssw]: %x\n", type, code); goto dopanic; } frame.f_pad = code & 0xffff; ucode = vftype; typ = SEGV_MAPERR; i = SIGSEGV; break; } } sv.sival_ptr = (void *)v; trapsignal(p, i, ucode, typ, sv); out: if ((type & T_USER) == 0) return; #ifdef M68040 wb_userret(p, &frame); #else userret(p); #endif } #if defined(M68040) #ifdef DEBUG struct writebackstats { int calls; int cpushes; int move16s; int wb1s, wb2s, wb3s; int wbsize[4]; } wbstats; char *f7sz[] = { "longword", "byte", "word", "line" }; char *f7tt[] = { "normal", "MOVE16", "AFC", "ACK" }; char *f7tm[] = { "d-push", "u-data", "u-code", "M-data", "M-code", "k-data", "k-code", "RES" }; char wberrstr[] = "WARNING: pid %d(%s) writeback [%s] failed, pc=%x fa=%x wba=%x wbd=%x\n"; #endif int writeback(struct frame *fp) { struct fmt7 *f = &fp->f_fmt7; struct proc *p = curproc; int err = 0; u_int fa; paddr_t pa; caddr_t oonfault = p->p_addr->u_pcb.pcb_onfault; #ifdef DEBUG if ((mmudebug & MDB_WBFOLLOW) || MDB_ISPID(p->p_pid)) { printf(" pid=%d, fa=%x,", p->p_pid, f->f_fa); dumpssw(f->f_ssw); } wbstats.calls++; #endif /* * Deal with special cases first. */ if ((f->f_ssw & SSW4_TMMASK) == SSW4_TMDCP) { /* * Dcache push fault. * Line-align the address and write out the push data to * the indicated physical address. */ #ifdef DEBUG if ((mmudebug & MDB_WBFOLLOW) || MDB_ISPID(p->p_pid)) { printf(" pushing %s to PA %x, data %x", f7sz[(f->f_ssw & SSW4_SZMASK) >> 5], f->f_fa, f->f_pd0); if ((f->f_ssw & SSW4_SZMASK) == SSW4_SZLN) printf("/%x/%x/%x", f->f_pd1, f->f_pd2, f->f_pd3); printf("\n"); } if (f->f_wb1s & SSW4_WBSV) panic("writeback: cache push with WB1S valid"); wbstats.cpushes++; #endif /* * XXX there are security problems if we attempt to do a * cache push after a signal handler has been called. */ pmap_kenter_pa((vaddr_t)vmmap, trunc_page((vaddr_t)f->f_fa), VM_PROT_WRITE); pmap_update(pmap_kernel()); fa = (u_int)&vmmap[m68k_page_offset(f->f_fa) & ~0x000f]; bcopy((caddr_t)&f->f_pd0, (caddr_t)fa, 16); pmap_extract(pmap_kernel(), (vaddr_t)fa, &pa); DCFL(pa); pmap_kremove((vaddr_t)vmmap, PAGE_SIZE); pmap_update(pmap_kernel()); } else if ((f->f_ssw & (SSW4_RW|SSW4_TTMASK)) == SSW4_TTM16) { /* * MOVE16 fault. * Line-align the address and write out the push data to * the indicated virtual address. */ #ifdef DEBUG if ((mmudebug & MDB_WBFOLLOW) || MDB_ISPID(p->p_pid)) printf(" MOVE16 to VA %x(%x), data %x/%x/%x/%x\n", f->f_fa, f->f_fa & ~0xF, f->f_pd0, f->f_pd1, f->f_pd2, f->f_pd3); if (f->f_wb1s & SSW4_WBSV) panic("writeback: MOVE16 with WB1S valid"); wbstats.move16s++; #endif if (KDFAULT(f->f_wb1s)) bcopy((caddr_t)&f->f_pd0, (caddr_t)(f->f_fa & ~0xF), 16); else err = suline((caddr_t)(f->f_fa & ~0xF), (caddr_t)&f->f_pd0); if (err) { fa = f->f_fa & ~0xF; #ifdef DEBUG if (mmudebug & MDB_WBFAILED) printf(wberrstr, p->p_pid, p->p_comm, "MOVE16", fp->f_pc, f->f_fa, f->f_fa & ~0xF, f->f_pd0); #endif } } else if (f->f_wb1s & SSW4_WBSV) { /* * Writeback #1. * Position the "memory-aligned" data and write it out. */ u_int wb1d = f->f_wb1d; int off; #ifdef DEBUG if ((mmudebug & MDB_WBFOLLOW) || MDB_ISPID(p->p_pid)) dumpwb(1, f->f_wb1s, f->f_wb1a, f->f_wb1d); wbstats.wb1s++; wbstats.wbsize[(f->f_wb2s&SSW4_SZMASK)>>5]++; #endif off = (f->f_wb1a & 3) * 8; switch (f->f_wb1s & SSW4_SZMASK) { case SSW4_SZLW: if (off) wb1d = (wb1d >> (32 - off)) | (wb1d << off); if (KDFAULT(f->f_wb1s)) *(long *)f->f_wb1a = wb1d; else err = copyout(&wb1d, (caddr_t)f->f_wb1a, sizeof(int)); break; case SSW4_SZB: off = 24 - off; if (off) wb1d >>= off; if (KDFAULT(f->f_wb1s)) *(char *)f->f_wb1a = wb1d; else { char tmp = wb1d; err = copyout(&tmp, (caddr_t)f->f_wb1a, sizeof(char)); } break; case SSW4_SZW: off = (off + 16) % 32; if (off) wb1d = (wb1d >> (32 - off)) | (wb1d << off); if (KDFAULT(f->f_wb1s)) *(short *)f->f_wb1a = wb1d; else { short tmp = wb1d; err = copyout(&tmp, (caddr_t)f->f_wb1a, sizeof(short)); } break; } if (err) { fa = f->f_wb1a; #ifdef DEBUG if (mmudebug & MDB_WBFAILED) printf(wberrstr, p->p_pid, p->p_comm, "#1", fp->f_pc, f->f_fa, f->f_wb1a, f->f_wb1d); #endif } } /* * Deal with the "normal" writebacks. * * XXX writeback2 is known to reflect a LINE size writeback after * a MOVE16 was already dealt with above. Ignore it. */ if (err == 0 && (f->f_wb2s & SSW4_WBSV) && (f->f_wb2s & SSW4_SZMASK) != SSW4_SZLN) { #ifdef DEBUG if ((mmudebug & MDB_WBFOLLOW) || MDB_ISPID(p->p_pid)) dumpwb(2, f->f_wb2s, f->f_wb2a, f->f_wb2d); wbstats.wb2s++; wbstats.wbsize[(f->f_wb2s&SSW4_SZMASK)>>5]++; #endif switch (f->f_wb2s & SSW4_SZMASK) { case SSW4_SZLW: if (KDFAULT(f->f_wb2s)) *(long *)f->f_wb2a = f->f_wb2d; else err = copyout(&f->f_wb2d, (caddr_t)f->f_wb2a, sizeof(int)); break; case SSW4_SZB: if (KDFAULT(f->f_wb2s)) *(char *)f->f_wb2a = f->f_wb2d; else { char tmp = f->f_wb2d; err = copyout(&tmp, (caddr_t)f->f_wb2a, sizeof(char)); } break; case SSW4_SZW: if (KDFAULT(f->f_wb2s)) *(short *)f->f_wb2a = f->f_wb2d; else { short tmp = f->f_wb2d; err = copyout(&tmp, (caddr_t)f->f_wb2a, sizeof(short)); } break; } if (err) { fa = f->f_wb2a; #ifdef DEBUG if (mmudebug & MDB_WBFAILED) { printf(wberrstr, p->p_pid, p->p_comm, "#2", fp->f_pc, f->f_fa, f->f_wb2a, f->f_wb2d); dumpssw(f->f_ssw); dumpwb(2, f->f_wb2s, f->f_wb2a, f->f_wb2d); } #endif } } if (err == 0 && (f->f_wb3s & SSW4_WBSV)) { #ifdef DEBUG if ((mmudebug & MDB_WBFOLLOW) || MDB_ISPID(p->p_pid)) dumpwb(3, f->f_wb3s, f->f_wb3a, f->f_wb3d); wbstats.wb3s++; wbstats.wbsize[(f->f_wb3s&SSW4_SZMASK)>>5]++; #endif switch (f->f_wb3s & SSW4_SZMASK) { case SSW4_SZLW: if (KDFAULT(f->f_wb3s)) *(long *)f->f_wb3a = f->f_wb3d; else err = copyout(&f->f_wb3d, (caddr_t)f->f_wb3a, sizeof(int)); break; case SSW4_SZB: if (KDFAULT(f->f_wb3s)) *(char *)f->f_wb3a = f->f_wb3d; else { char tmp = f->f_wb3d; err = copyout(&tmp, (caddr_t)f->f_wb3a, sizeof(char)); } break; case SSW4_SZW: if (KDFAULT(f->f_wb3s)) *(short *)f->f_wb3a = f->f_wb3d; else { short tmp = f->f_wb3d; err = copyout(&tmp, (caddr_t)f->f_wb3a, sizeof(short)); } break; #ifdef DEBUG case SSW4_SZLN: panic("writeback: wb3s indicates LINE write"); #endif } if (err) { fa = f->f_wb3a; #ifdef DEBUG if (mmudebug & MDB_WBFAILED) printf(wberrstr, p->p_pid, p->p_comm, "#3", fp->f_pc, f->f_fa, f->f_wb3a, f->f_wb3d); #endif } } p->p_addr->u_pcb.pcb_onfault = oonfault; /* * Any problems are SIGSEGV's */ if (err) err = SIGSEGV; return (err); } #ifdef DEBUG void dumpssw(ssw) u_short ssw; { printf(" SSW: %x: ", ssw); if (ssw & SSW4_CP) printf("CP,"); if (ssw & SSW4_CU) printf("CU,"); if (ssw & SSW4_CT) printf("CT,"); if (ssw & SSW4_CM) printf("CM,"); if (ssw & SSW4_MA) printf("MA,"); if (ssw & SSW4_ATC) printf("ATC,"); if (ssw & SSW4_LK) printf("LK,"); if (ssw & SSW4_RW) printf("RW,"); printf(" SZ=%s, TT=%s, TM=%s\n", f7sz[(ssw & SSW4_SZMASK) >> 5], f7tt[(ssw & SSW4_TTMASK) >> 3], f7tm[ssw & SSW4_TMMASK]); } void dumpwb(num, s, a, d) int num; u_short s; u_int a, d; { struct proc *p = curproc; paddr_t pa; int tmp; printf(" writeback #%d: VA %x, data %x, SZ=%s, TT=%s, TM=%s\n", num, a, d, f7sz[(s & SSW4_SZMASK) >> 5], f7tt[(s & SSW4_TTMASK) >> 3], f7tm[s & SSW4_TMMASK]); printf(" PA "); if (pmap_extract(p->p_vmspace->vm_map.pmap, (vaddr_t)a, &pa) == FALSE) printf(""); else { if (copyin((caddr_t)a, &tmp, sizeof(int)) == 0) printf("%lx, current value %lx", pa, tmp); else printf("%lx, current value inaccessible", pa); } printf("\n"); } #endif #endif /* * Process a system call. */ void syscall(code, frame) register_t code; struct frame frame; { caddr_t params; struct sysent *callp; struct proc *p; int error, opc, nsys; size_t argsize; register_t args[8], rval[2]; uvmexp.syscalls++; if (!USERMODE(frame.f_sr)) panic("syscall"); p = curproc; p->p_md.md_regs = frame.f_regs; opc = frame.f_pc; nsys = p->p_emul->e_nsysent; callp = p->p_emul->e_sysent; #ifdef COMPAT_SUNOS if (p->p_emul == &emul_sunos) { /* * SunOS passes the syscall-number on the stack, whereas * BSD passes it in D0. So, we have to get the real "code" * from the stack, and clean up the stack, as SunOS glue * code assumes the kernel pops the syscall argument the * glue pushed on the stack. Sigh... */ if (copyin((caddr_t)frame.f_regs[SP], &code, sizeof(register_t)) != 0) code = -1; /* * XXX * Don't do this for sunos_sigreturn, as there's no stored pc * on the stack to skip, the argument follows the syscall * number without a gap. */ if (code != SUNOS_SYS_sigreturn) { frame.f_regs[SP] += sizeof (int); /* * remember that we adjusted the SP, * might have to undo this if the system call * returns ERESTART. */ p->p_md.md_flags |= MDP_STACKADJ; } else p->p_md.md_flags &= ~MDP_STACKADJ; } #endif params = (caddr_t)frame.f_regs[SP] + sizeof(int); switch (code) { case SYS_syscall: /* * Code is first argument, followed by actual args. */ if (copyin(params, &code, sizeof(register_t)) != 0) code = -1; params += sizeof(int); /* * XXX sigreturn requires special stack manipulation * that is only done if entered via the sigreturn * trap. Cannot allow here, so make sure we fail. */ if (code == SYS_sigreturn) code = nsys; break; case SYS___syscall: /* * Like syscall, but code is a quad, so as to maintain * quad alignment for the rest of the arguments. */ if (callp != sysent) break; if (copyin(params + _QUAD_LOWWORD * sizeof(int), &code, sizeof(register_t)) != 0) code = -1; params += sizeof(quad_t); break; default: break; } if (code < 0 || code >= nsys) callp += p->p_emul->e_nosys; /* illegal */ else callp += code; argsize = callp->sy_argsize; if (argsize) error = copyin(params, (caddr_t)args, argsize); else error = 0; #ifdef SYSCALL_DEBUG scdebug_call(p, code, args); #endif #ifdef KTRACE if (KTRPOINT(p, KTR_SYSCALL)) ktrsyscall(p, code, argsize, args); #endif if (error) goto bad; rval[0] = 0; rval[1] = frame.f_regs[D1]; #if NSYSTRACE > 0 if (ISSET(p->p_flag, P_SYSTRACE)) error = systrace_redirect(code, p, args, rval); else #endif error = (*callp->sy_call)(p, args, rval); switch (error) { case 0: frame.f_regs[D0] = rval[0]; frame.f_regs[D1] = rval[1]; frame.f_sr &= ~PSL_C; /* carry bit */ break; case ERESTART: /* * We always enter through a `trap' instruction, which is 2 * bytes, so adjust the pc by that amount. */ frame.f_pc = opc - 2; break; case EJUSTRETURN: /* nothing to do */ break; default: bad: if (p->p_emul->e_errno) error = p->p_emul->e_errno[error]; frame.f_regs[D0] = error; frame.f_sr |= PSL_C; /* carry bit */ break; } #ifdef SYSCALL_DEBUG scdebug_ret(p, code, error, rval); #endif #ifdef COMPAT_SUNOS /* need new p-value for this */ if (error == ERESTART && (p->p_md.md_flags & MDP_STACKADJ)) frame.f_regs[SP] -= sizeof (int); #endif userret(p); #ifdef KTRACE if (KTRPOINT(p, KTR_SYSRET)) ktrsysret(p, code, error, rval[0]); #endif }